Structural elucidation of disinfection by‐products in treated drinking water

Publisher Website
Google Scholar
Abstract
Two unusual disinfection by‐products have been detected periodically in the gas chromatography/mass spectrometry (GC/MS) characterization analyses of semi‐volatile organics in treated drinking water. The electron ionization (EI) mass spectra contained mono‐chlorinated and mono‐brominated ions at m/z 107/109 and 151/153, respectively. Library searching techniques suggested mono‐halogenated butanol structures but no matches could be found. Positive ion chemical ionization (CI) spectra contained mono‐chlorinated and mono‐brominated ions at m/z 105/107 and 149/151, respectively. No [M + H]+ ions were initially observed. Accurate mass measurements confirmed the empirical formulae for the significant ions in the EI spectra and the mono‐halogenated butanol structures. Further CI experiments with other reagent gases and instruments revealed possible molecular weights of 139 and 183 Da, respectively. Tandem mass spectrometry (MS/MS) experiments in EI and CI were used to elucidate the fragmentation schemes. The two compounds have been tentatively identified as 1‐aminoxy‐1‐chlorobutan‐2‐ol and 1‐aminoxy‐1‐bromobutan‐2‐ol, respectively. Copyright © 2001 John Wiley & Sons, Ltd.